U.S. patent application number 15/478759 was filed with the patent office on 2017-10-12 for ultraviolet surface illumination system.
This patent application is currently assigned to Sensor Electronic Technology, Inc.. The applicant listed for this patent is Sensor Electronic Technology, Inc.. Invention is credited to Alexander Dobrinsky, Emmanuel Lakios, Michael Shur.
Application Number | 20170290934 15/478759 |
Document ID | / |
Family ID | 59999840 |
Filed Date | 2017-10-12 |
United States Patent
Application |
20170290934 |
Kind Code |
A1 |
Dobrinsky; Alexander ; et
al. |
October 12, 2017 |
Ultraviolet Surface Illumination System
Abstract
A diffusive ultraviolet illuminator is provided. The illuminator
can include a reflective mirror and a set of ultraviolet radiation
sources located within a proximity of the focus point of the
reflective mirror. The ultraviolet radiation from the set of
ultraviolet radiation sources is directed towards a reflective
surface located adjacent to the illuminator. The reflective surface
can diffusively reflect at least 30% the ultraviolet radiation and
the diffusive ultraviolet radiation can be within at least 40% of
Lambertian distribution. A set of optical elements can be located
between the illuminator and the reflective surface in order to
direct the ultraviolet radiation towards at least 50% of the
reflective surface.
Inventors: |
Dobrinsky; Alexander;
(Loudonville, NY) ; Shur; Michael; (Latham,
NY) ; Lakios; Emmanuel; (Mount Sinai, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sensor Electronic Technology, Inc. |
Columbia |
SC |
US |
|
|
Assignee: |
Sensor Electronic Technology,
Inc.
Columbia
SC
|
Family ID: |
59999840 |
Appl. No.: |
15/478759 |
Filed: |
April 4, 2017 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62319752 |
Apr 7, 2016 |
|
|
|
62330368 |
May 2, 2016 |
|
|
|
62356696 |
Jun 30, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 6/001 20130101;
G02B 19/0095 20130101; G02B 5/0891 20130101; G02B 6/02295 20130101;
G02B 3/08 20130101; G02B 6/0096 20130101; A61L 2/10 20130101; G02B
5/0284 20130101; G02B 5/10 20130101; G02B 19/0023 20130101 |
International
Class: |
A61L 2/10 20060101
A61L002/10; G02B 5/02 20060101 G02B005/02; G02B 6/02 20060101
G02B006/02; G02B 3/08 20060101 G02B003/08; F21V 8/00 20060101
F21V008/00; G02B 5/08 20060101 G02B005/08; G02B 5/10 20060101
G02B005/10 |
Claims
1. A system comprising: an illuminator including: a reflective
mirror; and a set of ultraviolet radiation sources located within a
proximity of a focus point of the reflective mirror, the set of
ultraviolet radiation sources configured to generate ultraviolet
radiation directed at the reflective mirror; a reflective surface
located adjacent to the illuminator; and a set of optical elements
located between the illuminator and the reflective surface, the set
of optical elements configured to direct an ultraviolet radiation
beam towards at least 50% of the reflective surface, wherein the
reflective surface diffusively reflects at least 30% of the
ultraviolet radiation.
2. The system of claim 1, wherein the reflective mirror is a
parabolic reflector.
3. The system of claim 1, wherein the set of optical elements
includes a first lens and a second lens, wherein a focal length of
each lens is comparable to a diameter of the ultraviolet radiation
beam.
4. The system of claim 3, wherein at least a portion of each lens
includes a Fresnel lens.
5. The system of claim 3, wherein the second lens is movable with
respect to the first lens.
6. The system of claim 1, wherein the set of ultraviolet radiation
sources are coupled by a diffusive waveguide structure.
7. The system of claim 6, wherein the diffusive waveguide structure
includes a plurality of roughness elements on a surface.
8. The system of claim 1, wherein the diffusive ultraviolet
radiation is directed towards a target surface and the diffusive
ultraviolet radiation is uniform over at least 20% of the target
surface.
9. The system of claim 1, wherein the set of optical elements
includes a total internal reflection lens.
10. The system of claim 1, further comprising a mesh located
between the reflective surface and a target surface, wherein the
mesh includes a photo-catalyst film.
11. The system of claim 1, further comprising a rail system,
wherein the rail system is configured to move the illuminator with
respect to a target surface.
12. A system comprising: an illuminator including: a reflective
mirror; and a set of ultraviolet radiation sources located within a
proximity of a focus point of the reflective mirror, the set of
ultraviolet radiation sources configured to generate ultraviolet
radiation directed at the reflective mirror; a reflective surface
located adjacent to the illuminator; and a set of optical elements
located between the illuminator and the reflective surface, the set
of optical elements configured to direct an ultraviolet radiation
beam towards at least 50% of the reflective surface, wherein the
reflective surface diffusively reflects the ultraviolet radiation
to within 40% of Lambertian distribution.
13. The system of claim 12, wherein the set of optical elements
includes a first lens and a second lens, wherein a focal length of
each lens is comparable to a diameter of the ultraviolet radiation
beam.
14. The system of claim 13, wherein at least a portion of each lens
includes a Fresnel lens.
15. The system of claim 13, wherein the second lens is movable with
respect to the first lens.
16. The system of claim 12, wherein set of ultraviolet radiation
sources are coupled by a diffusive waveguide structure.
17. The system of claim 12, wherein the diffusive ultraviolet
radiation is directed towards a target surface and the diffusive
ultraviolet radiation is uniform over at least 20% of the target
surface.
18. The system of claim 12, wherein the set of optical elements
includes a total internal reflection lens.
19. A system comprising: a set of illuminators, each illuminator
including: a reflective mirror; and a set of ultraviolet radiation
sources located within a proximity of a focus point of the
reflective mirror, the set of ultraviolet radiation sources
configured to generate ultraviolet radiation directed towards the
reflective mirror; a reflective surface located between the set of
illuminators; and a set of optical elements located between each
illuminator and the reflective surface, the set of optical elements
configured to direct an ultraviolet radiation beam towards at least
50% of the reflective surface, wherein the reflective surface
diffusively reflects the ultraviolet radiation to within 40% of
Lambertian distribution.
20. The system of claim 19, wherein the set of optical elements
includes a set of lenses, wherein a focal length of each lens is
comparable to a diameter of the ultraviolet radiation beam.
Description
REFERENCE TO RELATED APPLICATIONS
[0001] The current application claims the benefit of U.S.
Provisional Application No. 62/319,752, filed on 7 Apr. 2016, U.S.
Provisional Application No. 62/330,368, filed on 2 May 2016, and
U.S. Provisional Application No. 62/356,696, filed on 30 Jun. 2016,
all of which are hereby incorporated by reference. Aspects of the
current application are related to U.S. application Ser. No.
14/853,075, filed on 14 Sep. 2015, U.S. application Ser. No.
15/472,198, filed on 28 Mar. 2017, U.S. Pat. No. 9,034,271, filed
on 28 Aug. 2013, and U.S. Pat. No. 9,550,004, filed on 5 Sep. 2014,
all of which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] The disclosure relates generally to ultraviolet radiation,
and more particularly, to disinfecting a surface using ultraviolet
radiation.
BACKGROUND ART
[0003] The use of light diffusers is common in backlight
illumination, which is frequently used in liquid crystal displays
(LCDs). For visible light, the criterion of diffuser design is
significantly different than that for ultraviolet (UV) radiation.
This is largely related to the fact that UV transparent materials
are harder to manufacture than corresponding materials for visible
light. Further, the transparency of UV materials is typically
inferior to the transparency of materials to visible light. In
addition, UV transparent materials are more expensive than the
materials transparent to visible light.
[0004] Recently, various improvements to backlight visible light
illumination design have been proposed. For example, collimating
multi-layer optical film (CMOF) provides a cost efficient light
management for LCD backlights with integrated optical films. These
films provide diffusive capability to LCD backlight illuminators.
CMOF is based on multi-layer optical film technology that is used
to make current display films, such as dual brightness enhancement
film (DBEF), reflective polarizers, and enhanced specular reflector
(ESR) films. The CMOFs are used in a new backlight architecture
developed by 3M.TM. and branded as Air Guide. CMOF technology
combines two types of nanotechnologies: nanolayer optics and
ultra-low refractive index nanofoam. The CMOF film is attached
directly to the LCD panel, replacing several separate films used in
current light emitting diode (LED) backlight designs. The new
design uses a hollow cavity with no free-floating films and no
solid light guide. In the Air Guide design, light is spread through
the air of the cavity between the LCD panel and the highly
reflective film.
[0005] In another traditional design for diffusive wave guiding,
the LED lights are positioned at a side of the diffuser. The
diffuser is composed of several layers: a sheet with
micro-features, reflecting and light guiding sheets, and a
diffusive sheet followed by optional prismatic and other diffusive
sheets. For success of such a design, good light reflective and
light transparent materials have to be employed, which is difficult
to achieve for ultraviolet illumination.
SUMMARY OF THE INVENTION
[0006] The present invention considers another design utilizing
scattering surfaces for uniform UV illumination.
[0007] Aspects of the invention provide an ultraviolet diffusive
illuminator. The illuminator includes a reflective mirror and a set
of ultraviolet radiation sources located within a proximity of the
focus point of the reflective mirror. The ultraviolet radiation
from the set of ultraviolet radiation sources is directed towards a
reflective surface located adjacent to the illuminator. The
reflective surface diffusively reflects at least 30% the
ultraviolet radiation and the diffusive ultraviolet radiation is
within at least 40% of Lambertian distribution. A set of optical
elements can be located between the illuminator and the reflective
surface in order to direct the ultraviolet radiation towards at
least 50% of the reflective surface.
[0008] A first aspect of the invention provides a system
comprising: an illuminator including: a reflective mirror; and a
set of ultraviolet radiation sources located within a proximity of
a focus point of the reflective mirror, the set of ultraviolet
radiation sources configured to generate ultraviolet radiation
directed at the reflective mirror; a reflective surface located
adjacent to the illuminator; and a set of optical elements located
between the illuminator and the reflective surface, the set of
optical elements configured to direct an ultraviolet radiation beam
towards at least 50% of the reflective surface, wherein the
reflective surface diffusively reflects at least 30% of the
ultraviolet radiation.
[0009] A second aspect of the invention provides a system
comprising: an illuminator including: a reflective mirror; and a
set of ultraviolet radiation sources located within a proximity of
a focus point of the reflective mirror, the set of ultraviolet
radiation sources configured to generate ultraviolet radiation
directed at the reflective mirror; a reflective surface located
adjacent to the illuminator; and a set of optical elements located
between the illuminator and the reflective surface, the set of
optical elements configured to direct an ultraviolet radiation beam
towards at least 50% of the reflective surface, wherein the
reflective surface diffusively reflects the ultraviolet radiation
to within 40% of Lambertian distribution.
[0010] A third aspect of the invention provides a system
comprising: a set of illuminators, each illuminator including: a
reflective mirror; and a set of ultraviolet radiation sources
located within a proximity of a focus point of the reflective
mirror, the set of ultraviolet radiation sources configured to
generate ultraviolet radiation directed towards the reflective
mirror; a reflective surface located between the set of
illuminators; and a set of optical elements located between each
illuminator and the reflective surface, the set of optical elements
configured to direct an ultraviolet radiation beam towards at least
50% of the reflective surface, wherein the reflective surface
diffusively reflects the ultraviolet radiation to within 40% of
Lambertian distribution.
[0011] The illustrative aspects of the invention are designed to
solve one or more of the problems herein described and/or one or
more other problems not discussed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] These and other features of the disclosure will be more
readily understood from the following detailed description of the
various aspects of the invention taken in conjunction with the
accompanying drawings that depict various aspects of the
invention.
[0013] FIG. 1A shows an illustrative illuminator according to an
embodiment, FIG. 1B shows an illustrative electrical system, FIG.
1C shows an illustrative electrical diagram, and FIG. 1D shows a
prototype of an illuminator according to an embodiment.
[0014] FIGS. 2A and 2B show illustrative ultraviolet radiation
sources according to embodiments.
[0015] FIGS. 3A and 3B show an illustrative illuminator according
to an embodiment, while FIG. 3C shows an illustrative waveguide
according to an embodiment.
[0016] FIGS. 4A-4C show illustrative systems according to
embodiments.
[0017] FIGS. 5A and 5B show illustrative illuminators according to
embodiments.
[0018] FIGS. 6A and 6B show illustrative devices including an
illuminator according to embodiments.
[0019] FIG. 7 shows an illustrative system according to an
embodiment.
[0020] FIG. 8 shows an example of a Fresnel lens.
[0021] FIGS. 9A and 9B show an illustrative schematic of two lenses
within an illuminator according to an embodiment.
[0022] FIG. 10 shows a schematic of two lenses within an
illuminator.
[0023] FIG. 11 shows an illustrative waveguide according to an
embodiment.
[0024] FIG. 12 shows an illustrative waveguide according to an
embodiment.
[0025] FIG. 13 shows an illustrative waveguide according to an
embodiment.
[0026] FIG. 14 shows an illustrative system according to an
embodiment.
[0027] FIG. 15 shows an illustrative system according to an
embodiment.
[0028] FIG. 16 shows an illustrative system according to an
embodiment.
[0029] FIG. 17 shows an illustrative illuminator according to an
embodiment.
[0030] FIG. 18 shows an illustrative illuminator according to an
embodiment.
[0031] FIG. 19 shows illustrative electrical connections for an
illuminator according to an embodiment.
[0032] FIG. 20A shows an illustrative illuminator according to an
embodiment, while FIG. 20B shows an illustrative wave guide
according to an embodiment.
[0033] FIGS. 21A and 21B show portable devices that utilize
illustrative illuminators according to embodiments.
[0034] It is noted that the drawings may not be to scale. The
drawings are intended to depict only typical aspects of the
invention, and therefore should not be considered as limiting the
scope of the invention. In the drawings, like numbering represents
like elements between the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0035] As indicated above, aspects of the invention provide an
ultraviolet diffusive illuminator. The illuminator includes a
reflective mirror and a set of ultraviolet radiation sources
located within a proximity of the focus point of the reflective
mirror. The ultraviolet radiation from the set of ultraviolet
radiation sources is directed towards a reflective surface located
adjacent to the illuminator. The reflective surface diffusively
reflects at least 30% the ultraviolet radiation and the diffusive
ultraviolet radiation is within at least 40% of Lambertian
distribution. A set of optical elements can be located between the
illuminator and the reflective surface in order to direct the
ultraviolet radiation towards at least 50% of the reflective
surface.
[0036] As used herein, unless otherwise noted, the term "set" means
one or more (i.e., at least one) and the phrase "any solution"
means any now known or later developed solution. It is understood
that, unless otherwise specified, each value is approximate and
each range of values included herein is inclusive of the end values
defining the range. As used herein, unless otherwise noted, the
term "approximately" is inclusive of values within +/-ten percent
of the stated value, while the term "substantially" is inclusive of
values within +/-five percent of the stated value. Unless otherwise
stated, two values are "similar" when the smaller value is within
+/-twenty-five percent of the larger value.
[0037] Furthermore, as used herein, ultraviolet radiation/light
means electromagnetic radiation having a wavelength ranging from
approximately 10 nanometers (nm) to approximately 400 nm, while
ultraviolet-C (UV-C) means electromagnetic radiation having a
wavelength ranging from approximately 100 nm to approximately 280
nm, ultraviolet-B (UV-B) means electromagnetic radiation having a
wavelength ranging from approximately 280 to approximately 315
nanometers, and ultraviolet-A (UV-A) means electromagnetic
radiation having a wavelength ranging from approximately 315 to
approximately 400 nanometers. As also used herein, a
material/structure is considered to be "reflective" to ultraviolet
light of a particular wavelength when the material/structure has an
ultraviolet reflection coefficient of at least thirty percent for
the ultraviolet light of the particular wavelength and is highly
reflective when the material/structure has an ultraviolet
reflection coefficient of at least seventy percent. Furthermore, a
material/structure is considered to be "transparent" to ultraviolet
light of a particular wavelength when the material/structure allows
at least ten percent of the ultraviolet light, which is radiated at
a normal incidence to an interface of the layer, to pass there
through; highly transparent when at least thirty percent of the
radiation passes there through; and substantially transparent when
at least eighty percent of the radiation passes there through. In
an embodiment, the target wavelength of the radiation corresponds
to a wavelength of radiation emitted or sensed (e.g., peak
wavelength +/-five nanometers) by an active region of an
optoelectronic device during operation of the device.
[0038] Turning to the drawings, FIG. 1A shows an illustrative
illuminator 10 according to an embodiment. Although the illuminator
10 is shown as an elongated lamp, it is understood that this is for
exemplary purposes only and that the illuminator 10 can be any
shape. The illuminator 10 includes a set ultraviolet radiation
sources 12A-12E, each of which can be positioned at any location on
the illuminator 10. The illuminator 10 can also include a set of
sensors 14, 16. The set of ultraviolet radiation sources 12A-12E
can comprise any combination of one or more ultraviolet radiation
emitters. Examples of ultraviolet radiation emitters can include,
but are not limited to, high intensity ultraviolet lamps (e.g.,
high intensity mercury lamps), discharge lamps, ultraviolet LEDs,
super luminescent LEDs, laser diodes, and/or the like. In one
embodiment, the set of ultraviolet radiation sources 12A-12E can
include a set of LEDs manufactured with one or more layers of
materials selected from the group-III nitride material system
(e.g., Al.sub.xIn.sub.yGa.sub.1-X-YN, where 0.ltoreq.x, y.ltoreq.1,
and x+y.ltoreq.1 and/or alloys thereof). Additionally, the set of
ultraviolet radiation sources 12A-12E can comprise one or more
additional components (e.g., a wave guiding structure, a component
for relocating and/or redirecting ultraviolet radiation emitter(s),
etc.) to direct and/or deliver the emitted radiation to a
particular location/area, in a particular direction, in a
particular pattern, and/or the like. Illustrative wave guiding
structures include, but are not limited to, a waveguide, a
plurality of ultraviolet fibers, each of which terminates at an
opening, a diffuser, a light guiding layer, a light diffusing
layer, and/or the like.
[0039] It is understood that the number of ultraviolet radiation
sources 12A-12E illustrated in FIG. 1A and the other embodiments
depicted in the remaining figures is only illustrative. Those
skilled in the art will appreciate that any number of one or more
ultraviolet radiation sources may be located within the illuminator
10.
[0040] Each of the ultraviolet radiation sources 12A-12E can
operate at the same or different wavelengths. For example, one or
more of the ultraviolet radiation sources 12A-12E can have a peak
emission of approximately 280 nanometers (nm), while the remaining
ultraviolet radiation sources 12A-12E have a peak emission of
approximately 295 nm.
[0041] FIG. 1B shows an illustrative electrical system 18 for an
illuminator, such as the illuminator 10 shown in FIG. 1A, according
to an embodiment. The electrical system 18 is configured to deliver
a controlled power supply to the set of ultraviolet radiation
sources 12A-12E in order to adjust a plurality of attributes of the
ultraviolet radiation. For example, the wavelength, intensity, duty
cycle, duration, and/or the like, of each of the set of ultraviolet
radiation sources 12A-12E can be independently adjusted. Although
it is not shown, it is understood that the illuminator 10 can
include a set of sensors (e.g., fluorescent, temperature, humidity,
and/or the like) and visible cameras 14, 16 in order to monitor a
surface and/or an object located on the surface. The electrical
system 18 can include an electrical transforming device that can
transform a regular alternating current power source to a direct
current power source. As shown in FIG. 1B, the electrical system 18
can also include safety interlocks in order to manually shut down
power and protect a user from electrical shock, a controller to
adjust the power, time, duty cycle, and/or the like, for each of
the set of ultraviolet radiation sources 12A-12E (FIG. 1A), and an
LED driver controlled by the controller in order to deliver power
to the set of ultraviolet radiation sources 12A-12E according to
the target requirements for each ultraviolet radiation source
12A-12E. FIG. 1C shows an illustrative electrical diagram of the
system 18 shown in FIG. 1B. FIG. 1D shows an illustrative prototype
of the illuminator 10 shown in FIG. 1A. In an embodiment, the
sensor 14 can be a fluorescent sensor, infrared sensor, and/or can
comprise a visible camera. In an embodiment, the sensor 16 can
comprise a source of UV-A, deep blue or visible light. It is
understood that the illuminator 10 can comprise a data processing
unit capable of analyzing the sensed radiation and adjusting power
of the ultraviolet radiation sources to achieve the objective of
the illumination, wherein the objective can be a required intensity
of radiation, a set radiation dose at a target wavelength, and/or
control of biological dynamics, such as elimination of bacteria,
viruses, and/or mildew.
[0042] FIGS. 2A and 2B show illustrative ultraviolet radiation
sources 12A, 12B according to embodiments. In FIG. 2A, the
ultraviolet radiation source 12A includes an ultraviolet LED
emitter 20 and an optical element 22 directly bonded to a light
emitting surface of the ultraviolet LED emitter 20. The ultraviolet
radiation source 12A can also include a reflective mirror 24 that
is shaped to deliver a target distribution of intensity for the
ultraviolet radiation 26. In an embodiment, the reflective mirror
24 can be a parabolic reflector. In another embodiment, the
reflective mirror 24 can be a conical reflector. The reflective
mirror 24 can be formed of any reflective material, such as highly
polished aluminum, fluoropolymer, such as polytetrafluoroethylene
(PTFE, such as Teflon.RTM.), and/or the like, in order to direct
the ultraviolet radiation 26 out of the cylindrical enclosure 28
that encompasses the components of the ultraviolet radiation source
12A. The cylindrical enclosure 28 is transparent to ultraviolet
radiation and is formed of an ultraviolet transparent material,
such as a fluoropolymer, silicon dioxide (SiO.sub.2), and/or the
like. In an embodiment, only a part of the cylindrical enclosure 28
is transparent to ultraviolet radiation. For example, the
cylindrical enclosure 28 can comprise an ultraviolet reflective
enclosure 28 having an ultraviolet transparent window. The
enclosure 28 can comprise a reflective material such as aluminum,
fluoropolymer, and/or the like, while the ultraviolet transparent
window can comprise an ultraviolet transparent material, such as
fluoropolymer, silicon dioxide (SiO.sub.2), sapphire, calcium
fluoride (CaF.sub.2), magnesium fluoride (MgF.sub.2), and/or the
like. A lens element 30 can be located at a light emitting end of
the reflective mirror 24 and can be used to further direct the
ultraviolet radiation 26 emitted from the ultraviolet radiation
source 12A.
[0043] In an embodiment, as shown in the ultraviolet radiation
source 12B in FIG. 2B, a total internal reflection (TIR) lens 32
can be used to direct the ultraviolet radiation 26. A TIR lens 32
can be beneficial to the overall design of the ultraviolet
radiation source 12B due to the low losses as compared to a
reflective mirror. Regardless, in any embodiment, the lenses 30, 32
can be formed of an ultraviolet transparent material, such as
silicon dioxide (SiO.sub.2), sapphire, calcium fluoride
(CaF.sub.2), magnesium fluoride (MgF.sub.2), anodized aluminum
oxide (AAO), and/or the like. In an embodiment, the TIR lens 32 can
comprise a fluoropolymer that is transparent to ultraviolet
radiation. For example, the TIR lens 32 can comprise a
fluoropolymer that is at least 50% transparent to ultraviolet
radiation. In an embodiment, some portion of the lens 30 in the
ultraviolet radiation source 12A and/or the lens 32 in the
ultraviolet radiation source 12B can include Fresnel lenses. For
example, the concave portions of the lens 30, 32 can be replaces by
Fresnel lens. The table (Table 1) below shows exemplary power
intensities for an ultraviolet radiation source at specific
distances from the surface of an LED die. For example, the
ultraviolet radiation source can operate at about 6-10
microwatts/cm.sup.2 at a distance of approximately 10 cm.
TABLE-US-00001 TABLE 1 Distance Average Power Intensity Standard
(cm) (uW/cm.sup.2) Deviation 10 6-10 0.2-1.sup. 20 2-5 0.1-0.2 30
0.5-3.sup. 0.05-0.15
[0044] Turning now to FIG. 3A, an illustrative illuminator 40
according to an embodiment is shown. The illuminator 40 can
comprise a parabolic body 41 and a set of ultraviolet radiation
sources 42 located in the proximity of a focus point of the
parabolic body 41. The precision of positioning the set of
ultraviolet radiation sources 42 within a focal point can affect
the direction of the radiated light. The precise positioning of the
set of ultraviolet radiation sources 42 can be adjusted depending
on the distribution of the intensity at the target surface away
from the illuminator 40. The parabolic body 41 can include a
cylinder with a two dimensional parabolic cross section. FIG. 3B
shows a side view of the illuminator 40 including the parabolic
body 41 and a set of ultraviolet radiation sources 42 located at
the focus point. In an embodiment, the set of ultraviolet radiation
sources 42 can be coupled to a diffusive waveguide 44. As shown in
FIG. 3C, the diffusive waveguide 44 can be configured to radiate
ultraviolet radiation 48 from the set of ultraviolet radiation
sources 42 by leaking it out of the diffusive surface.
[0045] The diffusive waveguide 44 can be formed of an ultraviolet
transparent material, such as SiO.sub.2, fluoropolymer, CaF.sub.2,
MgF.sub.2, and/or the like. In an embodiment, the diffusive
waveguide 44 includes a plurality of roughness elements on a
surface that are configured to emit uniform ultraviolet radiation
through the waveguide 44. The plurality of roughness elements 44
can be micro-crystals or micro-domains of ultraviolet transparent
material, such as SiO.sub.2, sapphire, CaF.sub.2, MgF.sub.2, AAO,
and/or the like. In an embodiment, the diffusive waveguide 44 can
contain vacancies that are filled with a liquid, such as water. The
water can include diffusive domains that are configured to scatter
radiation. In an embodiment, at least one sensor 46 (e.g., an
ultraviolet LED sensor) can be coupled to the diffusive waveguide
44. The parabolic body 41 is formed of a highly reflective
material, such as polished aluminum, and/or the like. In an
embodiment, the parabolic body 41 has a high specular reflectivity
to ultraviolet radiation, wherein high means at least 70%
specularly reflective.
[0046] Turning now to FIG. 4A, an illustrative system 50 including
an illuminator, such as the illuminator 40 shown in FIG. 3A,
according to an embodiment is shown. However, it is understood that
the system 50 can include any of the embodiments of the illuminator
described herein. Regardless, as discussed in conjunction with FIG.
3A, the illuminator 40 includes a parabolic body 41 and a set of
ultraviolet radiation sources 42 located at or in the proximity of
the focus point of the parabolic body 41 in order to form a
collimated beam of ultraviolet radiation 52. It is understood that
the collimated beam of ultraviolet radiation 52 is not perfectly
collimated and the degree of collimation depends on the target
application of the illuminator 40. In an embodiment, the
illuminator 40 is configured to direct the collimated beam of
ultraviolet radiation 52 to impinge on a reflective surface 54 and
cover at least 50% of the reflective surface 54. It is understood
that this can be accomplished by adjusting the attributes of the
illuminator 40 (e.g., how the ultraviolet radiation 52 is reflected
from the parabolic body 41) and/or by changing the direction/angle
of the illuminator 40. In an embodiment, the direction of the
collimated beam of ultraviolet radiation 52 is substantially
tangential with the reflective surface 54. The reflective surface
54 can be formed of a highly diffusively reflective material, such
as a fluoropolymer, such as polytetrafluoroethylene (PTFE, such as
Teflon.RTM.), rough aluminum, rough sapphire, rough
SiO.sub.2/aluminum mirror, fluorinated ethylene propylene
co-polymer (EFEP), ethylene tetrafluoroethylene (ETFE), expanding
polytetrafluoroethylene (ePTFE) membrane (e.g., GORE.RTM. DRP.RTM.
Diffuse Reflector Material), and/or the like. In an embodiment, the
reflective surface 54 reflects at least 30% of the ultraviolet
radiation 52. In a more specific embodiment, the reflective surface
54 reflects at least 50% of the ultraviolet radiation 52. The
reflective surface 54 is configured to provide a uniform diffusive
reflection 56. The uniform diffusive reflection 56 is within at
least 40% of a Lambertian distribution.
[0047] It is understood that the position and direction of the
collimated beam of ultraviolet radiation 52 can be varied to
provide a uniform diffusive reflection 56 off of the reflective
surface 54. However, a system can also include additional optical
elements to control and direct the ultraviolet radiation. For
example, FIG. 4B shows an illustrative system 60 according to an
embodiment. In the system 60, a set of lenses 66 can be used to
direct the collimated beam of ultraviolet radiation 62 at the
reflective surface 64. Although only one lens 66 is shown, it is
understood that the system 60 can include any number of lenses. In
an embodiment, it is understood that any and all of the lenses can
be removed and the system 60 can remain operational. Each lens in
the set of lenses 66 has a focal length that is comparable to the
diameter of the collimated beam of ultraviolet radiation 62. In an
embodiment, the diffusive reflection 56 (FIG. 4A) off of the
reflective surface 64 is uniform over at least 20% of a target
surface 68, which is located a distance H1 away from the reflective
surface 64. In an embodiment, the illuminator can comprise height H
and width L and can be designed such that overall illuminator
volume is small. In an embodiment, H is smaller than L and can be
at most 10% of L for an illuminator that designed to irradiate a
large area without taking significant amount of physical space. In
an embodiment, with the distance H1 between the reflective surface
64 and the target surface 68 as a known parameter, the diffusive
and/or reflective properties of the reflective surface 64 can vary
laterally in order to provide a more uniform diffusive reflection
56 (FIG. 4A). Other aspects of the system 60 can be changed to
improve the uniformity of the diffusive reflection 56, including,
but not limited to, the direction of the collimated beam of
ultraviolet radiation 62 (e.g., by changing the direction of the
illuminator 40), the position and/or orientation of optical
elements within the system 60, such as the lens 66, and/or the
like. In an embodiment, the diffusive reflection 56 can be variable
by changing the orientation of the illuminator 40 so that the
collimated beam of ultraviolet radiation 62 is only directed at a
portion of the reflective surface 64.
[0048] FIG. 4C shows an illustrative system 70 including a first
illuminator 40A and a second illuminator 40B according to an
embodiment. Similar to the illuminator 40 shown in FIG. 3A, each of
the illuminators 40A, 40B includes a parabolic body 41 and a set of
ultraviolet radiation sources 42 located in or in the proximity of
the focus point of the parabolic body 41 in order to form a
collimated beam of ultraviolet radiation 46. Each illuminator 40A,
40B also includes a set of lenses 76A-C that are configured to
further collimate the ultraviolet radiation 72 and direct it
towards a reflective surface 74. The reflective surface 74 can be
similar to the reflective surfaces 54, 64 shown in FIGS. 4A and 4B
and can be formed of a highly diffusively reflective material, such
as a fluoropolymer, such as polytetrafluoroethylene (PTFE, such as
Teflon.RTM.), rough aluminum, fluorinated ethylene propylene
co-polymer (EFEP), ethylene tetrafluoroethylene (ETFE), expanding
polytetrafluoroethylene (ePTFE) membrane (e.g., GORE.RTM. DRP.RTM.
Diffuse Reflector Material), and/or the like. The reflective
surface 74 can reflect at least 50% of the ultraviolet radiation
72. In this embodiment, instead of changing an angle of the
illuminators 40A, 40B, the reflective surface 74 is substantially a
V-shape, so that the collimated beam of ultraviolet radiation 72
from each illuminator 40A, 40B can be directed at the reflective
surface 74. It is understood a system can include more than two
illuminators and the reflective surface can include additional
facets/surfaces in order to diffusively reflect the ultraviolet
radiation of each illuminator.
[0049] FIG. 5A shows a three-dimensional view of an illustrative
illuminator 80 with a reflective surface 84 according to an
embodiment, while FIG. 5B shows an illustrative system 90 including
the illuminator 80 according to an embodiment. The illuminator 80
includes a set of ultraviolet radiation sources 82 that can be
coupled to a diffusive waveguide 83, similar to the diffusive
waveguide 44 shown in FIG. 3A. Although only three ultraviolet
radiation sources 82 are shown in FIG. 5A, it is understood that
the illuminator 80 can include any number of ultraviolet radiation
sources. Referring now to FIGS. 5A and 5B, in an embodiment, the
set of ultraviolet radiation sources 82 can be located adjacent to
an elongated TIR lens 86 that is configured to form a collimated
beam of ultraviolet radiation 92 from the set of ultraviolet
radiation sources 82 onto a reflective surface 84 to provide a
diffusive reflection 94. In an embodiment, the system 90 can also
include a mesh 96 that is configured to promote diffusive
scattering and recycling of the ultraviolet radiation. The mesh 96
is formed of an ultraviolet reflective material and can include
aluminum, PFTE (e.g., Teflon.RTM.) and/or the like. The spacing of
the portions of the mesh 96, and the structure of the mesh 96 is
selected to form a uniform radiation over the target surface within
at least 50% of the area covered by the illuminator 80, wherein the
uniformity means that the difference in intensity of radiation of
maximum and minimum intensity values does not exceed 50%. In an
embodiment, the mesh 96 can include a photo-catalyst film, such as
titanium dioxide (TiO.sub.2) that can improve disinfection of the
ambient when exposed to ultraviolet radiation, aid in the
elimination of unwanted odors present in the ambient, and/or the
like. The photo-catalyst film can be selected and radiated by UVA
radiation, as UVA radiation (e.g., wavelengths less than
approximately 390 nm) is efficiently absorbed by typical
photo-catalysts (TiO.sub.2). UVA ultraviolet radiation sources can
be generated using methods in the visible LED technology, and, as
known in the art, UVA devices have significant advantages in
reliability power and efficiency.
[0050] FIGS. 6A and 6B show illustrative devices including an
illuminator according to embodiments. FIG. 6A shows a drawer 100
including a system 60 (as shown in FIG. 4B) configured to disinfect
the interior of the drawer 100. FIG. 6B shows a cash register 102
including a system 60 configured to disinfect the interior of the
cash register 102. In both embodiments, the illuminator in the
system 60 is capable of a small height (e.g., H in FIG. 4B) and a
large length (e.g., L in FIG. 4B). It is understood that the system
60 illustrated in FIGS. 6A and 6B is only illustrative and the
devices 100, 102 can include any embodiment of the systems
described herein.
[0051] In an embodiment, the orientation of the optical elements
with respect to one another in an illuminator can be changed. For
example, FIG. 7 shows an illustrative system 120 according to an
embodiment. The illuminator 40 is similar to the illuminator shown
in FIG. 3A and includes a parabolic body 41 and a set of
ultraviolet radiation sources 42 located in a focus point of the
parabolic body 41. However, the system 120 includes a reflective
surface 124 that is located at an angle in order to reflect the
ultraviolet radiation 122 from the illuminator 40 towards a set of
lenses 126A, 126B. Although only two lenses 126A, 126B are shown,
it is understood that the system 120 can include any number of
lenses. The set of lenses 126A, 126B are separated by a distance D1
and the second lens 126B is separated from a target surface 130 by
a distance D2. The set of lenses 126A, 126B can be formed of an
ultraviolet transparent material such as sapphire, SiO.sub.2, a
fluoropolymer, calcium fluoride (CaF.sub.2), magnesium fluoride
(MgF.sub.2), anodized aluminum oxide (AAO), and/or the like.
[0052] If the set of lenses 126A, 126B are formed of a
fluoropolymer material, the set of lenses 120A, 120B can be Fresnel
lenses that are manufacturing through imprinting. An example of a
Fresnel lens 126 is shown in FIG. 8. This Fresnel lens 126 is
profiled in one direction.
[0053] Returning to FIG. 7, the distances D1, D2 can vary by moving
the position of the second lens 126B with respect the first lens
126A and the target surface 130. In an embodiment, the second lens
126B can be moved using a knob 134. However, it is understood that
the knob 134 is for exemplary purposes only and that the second
lens 126B can be moved using any method. The system 120 can be
designed to be installed along with the target surface 130 (e.g., a
shelf) in order to disinfect and/or preserve the target surface 130
and a set of items 132 located on the target surface 130 using the
reflected ultraviolet radiation 128 from the set of lenses 126A,
126B. By adjusting the knob 134, the reflected ultraviolet
radiation 128 can be uniform across the target surface 130. In an
embodiment, adjusting the knob 134 results in a resolution of at
least 1 mm. In an embodiment, the target intensity variation does
not exceed 50% over the target surface 130. In an embodiment, for
the preservation of plants, the system 120 can operate at
wavelengths between approximately 280 nm and approximately 310 nm,
and for the disinfection purposes, the system 120 can operate at
wavelengths between approximately 210 nm and approximately 280 nm.
FIGS. 9A and 9B show the two illustrative lenses 126A, 126B from
FIG. 7 according to an embodiment. The total focal length of both
lenses 126A, 126B is given by the equation:
1/f=1/f.sub.1+1/f.sub.2-d/(f.sub.1 f.sub.2), where f is the total
focal length of both lenses, f.sub.1 is the focal length of the
first lens 126A, f.sub.2 is the focal length of the second lens
126B, and d is the distance between the two lenses 126A, 126B. It
is clear that for f.sub.1=f.sub.2, and d=2f.sub.1 the resulting
light exiting the two lenses is parallel, whereas for d=f.sub.1 the
two lens structure has the same focal point as a single lens. From
this, it follows that the two lens structure can yield high
focusing sensitivity for cases when f.sub.1 is small, such as
f.sub.1.about.1 cm. Turning to FIG. 10, an illustrative schematic
of two lenses according to an embodiment is shown. Consider a
distance between an ultraviolet radiation source and a target
surface being S (e.g., S can be 1/2 meter). The radius of the beam
r is significantly smaller (on the order of 1 cm). In general, the
angle .theta. can vary between approximately 20 degrees to
approximately 60 degrees. In all cases:
R L = tan .theta. , ##EQU00001##
with tan .theta..about.0.2 . . . 2 with L=.about.{R/0.2 . . . R/2}.
Therefore, in general, L.about.R. Since the focal point distance f
is comparable to r (at least for the single lens, and .theta.=45
degrees), S.about.L. By placing the second lens (having the same
focal distance) in the focal point of the first lens, this produces
no effect of the second lens: Consider:
1 f = 1 f 1 + 1 f 1 - f 1 f 1 f 1 = 1 f 1 . ##EQU00002##
Therefore, the second lens makes no effect and no additional
focusing is required. Placing the second lens at a distance 2f1
produces a parallel beam:
1 f = 1 f 1 + 1 f 1 - 2 f 1 f 1 f 1 = 0. ##EQU00003##
Therefore, moving a lens one focal point of the first lens changes
the focus from purely defocused to purely focused. Choosing a lens
with sufficient small focus length (e.g., f.about.r.about.1/cm)
allows small changes in the motion of the second lens to lead in
large focusing effects of the intensity. Use of a single lens does
not allow such sensitivity of focusing, requiring the lens to move
on the order L to yield correct focusing. It is important to choose
a lens with a sufficiently small focal length (e.g., f.about.1
cm).
[0054] It is understood that other embodiments of a diffusive
waveguide can be located in the proximity of the focus point of a
parabolic body. FIG. 11 shows an illustrative waveguide 200
according to an embodiment. The waveguide 200 comprises a set of
ultraviolet radiation sources 202A, 202B, a reflective layer 220, a
propagating region 240, and a plurality of highly diffusive regions
250A-C. The propagation region 240 can comprise an ultraviolet
transparent material such as fluoropolymer, SiO.sub.2,
Al.sub.2O.sub.3, CaF.sub.2, MgF.sub.2, and/or the like. It is
understood that the waveguide 200 can be non-uniform in propagating
and diffusive characteristics. In an embodiment, the waveguide 200
can include a set of mirror elements. For example, the waveguide
200 can include a parabolic body in one of the layers. The distance
L between two sources 202A, 202B is selected to be smaller than the
attenuation distance within the propagating region 240, wherein
attenuation distance is a distance from the source 202A, 202B where
the intensity of light is decreased by 60%.
[0055] FIG. 12 shows an illustrative wave guiding structure 300
according to an embodiment. The wave guiding structure 300 is
coupled to an ultraviolet radiation source 312 and includes
multiple layers 322A-322G. Some of the layers (e.g., layers 322A,
322C, 322E, 322G) each formed of a transparent material and
sufficiently thin to provide a desired level of transparency, while
other layers (e.g., layers 322B, 322D, 322F) are filled with a
transparent fluid. The wave guiding structure 300 also includes an
emission surface 314 through which diffused light 320 exits. The
wave guiding structure 300 can further include diffusive elements
318A, 318C associated with at least one of the plurality of layers.
Each diffusive element 318A, 318C can diffuse the light 320 to
within forty percent of Lambertian distribution. The diffusive
elements 318A, 318C can be arranged based on a desired uniformity
of the diffused light 320 at a target distance corresponding to a
surface to be illuminated. Aspects of this embodiment are related
to U.S. patent application Ser. No. 14/853,0175, filed on 14 Sep.
2015 and U.S. Pat. No. 9,550,004, filed on 5 Sep. 2014, both of
which are incorporated by reference.
[0056] FIG. 13 shows an illustrative wave guiding layer 400
according to an embodiment. Aspects of the wave guiding layer 400
are related to U.S. patent application Ser. No. 15/472,198, filed
on 28 Mar. 2017, which is incorporated by reference. The wave
guiding layer 400 includes a set of pluggable ultraviolet radiation
sources 402A-402C. The pluggable ultraviolet radiation sources
402A-402C can provide a convenient embodiment for replacing the
ultraviolet radiation sources 402A-402C if they have failed. In an
embodiment, a socket can be developed to plug in different
ultraviolet radiation sources 402A-402C depending on the target
application. For instance, the ultraviolet radiation sources of
different wavelength and intensity can be allowed to be plugged
into a socket with the control power system capable of delivering
sufficient current for operation of such ultraviolet radiation
devices.
[0057] FIG. 14 shows an illustrative system 500 according to an
embodiment. In this embodiment, the system 500 is in a vertical
arrangement with respect to a target surface 540. The system 500
includes an illuminator 502 (e.g., a parabolic body 510 and a set
of ultraviolet radiation sources 512 located in the proximity of a
focus point of the parabolic body 510). The system 500 can also
include a set of lenses 514A, 514B located between the set of
ultraviolet radiation sources 512 and the target surface 540.
Similar to the illuminator shown in FIG. 7, the position of the set
of lenses 514A, 514B can be adjusted in order to change the
ultraviolet radiation directed onto the target surface 540. In an
embodiment, the set of lenses 514A, 514B are circular lenses and
the target surface 540 is a circular surface. It is understood that
the second lens 514B is not necessary in this embodiment.
[0058] FIG. 15 shows an illustrative system 600 including an
illuminator 640 according to an embodiment. The illuminator 640 can
be any illuminator described herein. That is, the illuminator 640
can include any number of sources, lenses, mirrors, reflective
surfaces, and/or the like, as discussed herein. In an embodiment,
the illuminator 640 can include a lens formed of a fluoropolymer.
In another embodiment, the illuminator 640 can include a Fresnel
lens. The illuminator 640 is attached to a rail system 620 that
allows the illuminator 640 to move in any direction. The system 600
includes a shelf 660 including a plurality of items 662. By
allowing the illuminator 640 to move in any direction over the
shelf 660, the illuminator 640 can target specific areas and/or
items 662 within the shelf 660.
[0059] FIG. 16 shows an illustrative system including an
ultraviolet radiation system 800 according to an embodiment. The
computer system 820 is configured to control the ultraviolet
radiation source 812 to direct ultraviolet radiation 813 into a
storage area 854 of a storage device 852, within which a set of
items 856 are located. The ultraviolet radiation source 812 can
include aspects of an illuminator described herein (e.g., the
illuminator 40 in FIG. 3A). The feedback component 814 is
configured to acquire data used to monitor a set of current
conditions of the storage area 854 and/or the items 856 over a
period of time. As illustrated, the feedback component 814 can
include a plurality of sensing devices 816, each of which can
acquire data used by the computer system 820 to monitor the set of
current conditions.
[0060] The feedback component 814 is configured to provide the data
to a computer system 820 in order to adjust attributes of the
ultraviolet radiation 813 based on the storage area 854 and/or the
items 856 within the storage area 854. The feedback component 814
uses visual cameras, chemical sensors, mechanical sensors, infrared
(IR) sensors, visible sensors, and/or UV sensors for detecting
changes within the storage area 854 and/or the set of items 856. In
an embodiment, the logic unit 817 receives data from a set of
sensing devices 816 and provides data corresponding to the set of
conditions of the storage area 854 and/or items 856 located in the
storage area 854 for processing by the computer system 820. In a
more particular embodiment, the computer system 820 can provide
information corresponding to the currently selected operating
configuration 850 for use by the feedback component 814. For
example, the logic unit 817 can adjust the operation of one or more
of the sensing devices 816, operate a unique subset of the sensing
devices 816, and/or the like, according to the currently selected
operating configuration 850. In response to data received from the
feedback component 814, the computer system 820 can automatically
adjust and control one or more aspects of the ultraviolet radiation
813 generated by the ultraviolet radiation source 812 according to
the currently selected operating configuration 850. The aspects of
the ultraviolet radiation 813 include a direction, an intensity, a
pattern, a spectral power, a duration, and/or the like.
[0061] The plurality of operating configurations 850 can include a
disinfection operating configuration, a storage life preservation
operating configuration, and an ethylene decomposition operating
configuration. Each operating configuration 50 includes a unique
combination of: a target intensity, a target peak wavelength, and a
target pattern for the ultraviolet radiation. The storage life
preservation operating configuration can require an ultraviolet
wavelength that is between approximately 285 nm to approximately
305 nm. In an embodiment, the target wavelength the storage life
preservation operating configuration is approximately 290 nm peak
emission of a relatively lower intensity substantially continuous
radiation. For example, an illustrative intensity range can be
between approximately 0.1 milliwatt/m.sup.2 and approximately 1000
milliwatt/m.sup.2. In an embodiment, the intensity for the
ultraviolet radiation in the storage life preservation operating
configuration can be approximately 400 microwatts/cm.sup.2. In a
more specific illustrative embodiment, the ultraviolet LEDs can
direct ultraviolet radiation having an intensity of a few (e.g.,
1-3) microwatts/cm.sup.2 for approximately seven days within an
enclosure that does not allow ultraviolet radiation to escape, such
as an aluminum tube.
[0062] The disinfection operating configuration can require any
subset of ultraviolet wavelengths in the range of ultraviolet
wavelengths (e.g., between approximately 10 nm and approximately
400 nm) and higher intensity levels. In an embodiment, the
intensity range can be between approximately 1 milliwatt/m.sup.2
and approximately 10 watt/m.sup.2. In a more specific embodiment,
the ultraviolet wavelength and intensity levels for the
disinfection operating configuration can be between approximately
250 nm to approximately 290 nm and approximately 20
microwatt/cm.sup.2 or higher, respectively, and the ultraviolet
light can be applied for approximately 20 minutes. In this case,
the dosage of ultraviolet radiation for the disinfection operating
configuration can be approximately 24 milliJoule/cm.sup.2. However,
it is understood that this is only illustrative and a dosage can be
at least 16 miliJoule/cm.sup.2. The ethylene decomposition
operating configuration an ultraviolet wavelength range of
approximately 285 nm to approximately 305 nm. In an embodiment, the
intensity range can be between approximately 1 milliwatt/m.sup.2
and approximately 1000 watt/m.sup.2.
[0063] Additional aspects of the feedback component are related to
U.S. Pat. No. 9,034,271, filed 28 Aug. 2013, which is hereby
incorporated by reference.
[0064] In any of the embodiments, it is understood that several
ultraviolet radiation sources can be included in the same
illuminator and a control system can independently operate each
ultraviolet radiation source. In addition, the system can include
any number of sensors, such as an ozone sensor that is configured
to monitor ozone levels in the ambient, a humidity sensor that is
configured to monitor the humidity levels in the ambient, a
temperature sensor, a chemical sensor (e.g., CO.sub.2 sensor)
and/or the like. Furthermore, the system can control attributes of
the ambient (e.g., using the environmental control component 818).
For example, the system can include a storage container with an
illuminator according to one of the embodiments discussed herein
for disinfecting the storage container and the storage container
can include means for incorporating chemicals (e.g., baking soda
and/or the like) to control the odor within the storage
container.
[0065] It is further understood that environmental factors such as
ambient temperature, air pressure, presence of ethylene and other
factors can affect operation of the system. In an embodiment, the
system can be designed to prolong the preservation of produce at
room temperature (e.g., temperatures of about 70 Fahrenheit),
refrigerator temperature of about 32-40 Fahrenheit, or at
temperatures in the range between 32-70 F. In all cases, the system
can employ UV radiation at a broad range of approximately 250 nm to
approximately 380 nm, with produce preservation radiation in the
range of approximately 285 nm to approximately 300 nm,
sterilization UVC radiation with a peak radiation of approximately
270 nm to approximately 280 nm, and UVA radiation for disinfection
using a photo-catalyst (e.g., TiO.sub.2). In addition, UV radiation
at various wavelengths can be employed for deactivation of
ethylene. Furthermore, the UV radiation and sensing by the sensing
devices 816 can be employed for detecting ozone levels within the
ambient.
[0066] FIG. 17 shows an illustrative illuminator 900 according to
an embodiment. The illuminator 900 can be configured to uniformly
illuminate a rectangular area 910. In an embodiment, each
illuminator 900 is designed to illuminate an area of
A.sub.o=W.sub.o*L.sub.o, where W.sub.o is the width and L.sub.o is
the length of the illuminator 900. For an arbitrary area A, the
number of illuminators is calculated by evaluating N=A/A.sub.0.
Alternatively, if the shelf is of the size W.sub.1*L.sub.1 then the
number of illuminators can be estimated by:
W.sub.1/W.sub.0*L.sub.1/L.sub.0. The rectangular region 910 that
can be adequately irradiated by illuminator 900. The shelf 920 can
be subdivided by a number of such areas 900 for thorough
irradiation. It is understood that the embodiments of the
illuminator described herein can be similar to a fluorescent tube.
FIG. 18 shows an illustrative illuminator 1000 that is configured
to look similar to a fluorescent tube. FIG. 19 shows illustrative
electrical connections 1010 for an illuminator 1000. Therefore, the
illuminator 1000 can be interchangeable with fluorescent tubes with
similar connections 1010. FIG. 20A shows an illustrative
illuminator 1000 designed to have connections similar to that of a
fluorescent tube that has connections 1010 (e.g., T2, T4, T5, T8,
T9, T10, T12, T17, PG17). For example, the connection 1010 is a T8
connection. In an embodiment, the exterior of the illuminator 1000
is a diffusive UV transparent fluoropolymer. In FIG. 20B, an
illustrative illuminator 1000 according to an embodiment is shown.
The illuminator 1000 can include waveguide elements and a
transparent diffusive powder-like material on an exterior surface.
FIGS. 21A and 21B show a plurality of portable containers, each of
which can include one or more illuminators 1000 as discussed
herein. For example, FIG. 21A shows stackable crates that can
include at least one illuminator 1000, while FIG. 21B shows a
storage container with at least one illuminator 1000.
[0067] The foregoing description of various aspects of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed, and obviously, many
modifications and variations are possible. Such modifications and
variations that may be apparent to an individual in the art are
included within the scope of the invention as defined by the
accompanying claims.
* * * * *